Vehicle hoist



Oct. 3, 1950 H. D. SMITH 2,524,237

VEHICLE HOIST Filed April 9, 1948 3 Sheets-Sheet 1 X INVENTOR- 3 Sheets-Sheet 2 H. D. SMITH VEHICLE HOIST Oct. 3, 1950 Filed April 9, 1948 INVENTOR. Harry 0. Smii/L H. D. SMITH VEHICLE HOIS'I Oct. 3, 1950 3 Sheets-Sheet 5 Filed April 9, 1948 Patented Oct. 3, 1950 UNITED STATES PATENT OFFICE VEHICLE HOIST Harry D. Smith, Philadelphia, Pa., assignor to Globe Hoist Company, Des Moines, Iowa, a corporation of Iowa This invention relates generally to vehicle hoists and in particular to a closure means for a vehicle hoist having a lift member mounted in a floor pit for movement to a lowered position below the level of the floor surface. The use of what might be termed a pit mounted vehicle hoist provides for a covering of the floor pit, when the hoist is in its lowered position, so that the floor space occupied by the hoist is free and unobstructed for the travel of automobiles and portable service equipment thereover.

An object of this invention is to provide an improved vehicle hoist of pit mounted type.

A further object of this invention is to provide a pit closure means for a pit mounted hoist, in which the closure means are movable to their open positions prior tothe movement of a the hoist from a lowered or raised position therefor, so that the pit is always open to receive the hoist or to permit the hoist being raised therefrom.

Another object of this invention is to provide a pit closure means for a pit mounted hoist of full hydraulic type in which air-operated means for moving the closure means to an open position is actuated concurrently with the supply of air to, or the release of air from, the usual oil reservoir adapted to supply oil under pressure to the hoist lift member.

Still another object of this invention is to provide a pit mounted hoist of full hydraulic type having an oil reservoir adapted to receive air under pressure to raise the hoist lift member, in which pit cover members are operable in response to the supply of air to the oil reservoir so as to be in their open positions when the hoist is being moved into or out of the pit, and in their closed positions at all other times.

A feature of this invention is found in the provision of a pit mounted hoist of full-hydraulic type in which a pair of oppositely arranged pit cover members are pivotally supported on side Walls of the pit for movement toward each other to closing positions therefor. A rockshaft, within the pit, is connected with the cover members such that the covers are concurrently pivoted in response to a rocking movement of the shaft. Air-operated means are adapted to rock the shaft in one direction to move the cover members to their open positions, and yieldable means act on the rock shaft in an opposite direction to move the cover members to their closed positions. A source of air under pressure is connected with an oil reservoir for the hoist lift member and with the air-operated means for the rock shaft, through a valve structure having a single control lever and constructed and arranged such that air is supplied to the air-operated means concurrently with the supply of air to or the release of air from the reservoir, whereby the cover members are moved to their open positions Whenever the hoist is being lowered into or raised from the floor pit.

Further objects, features and advantages of this invention will appear from the following description when taken in connection with the accompanying drawings, in which:

Fig. 1 is a perspective view of a vehicle lift of two-post type embodying the pit closure means of this invention with the rear hoist thereof, with certain parts broken away to more clearly show the construction and assembly of the closure means;

Fig. 2 is an enlarged planview of the rear hoist with the closure means in its pit closing position and showing parts broken away;

Fig. 3 is a fragmentary perspective view of the rear hoist looking in a direction generally upwardly and forwardly from a position within the pit, and with the closure means in a closed posi tion ' the front and rear hoists of the vehicle lift;

Fig. 6 is a perspective view of an air valve structure forming part of the hoist air system;

Fig. '7 is a diagrammatic showing of the air With reference to the drawings, there is shown in Fig. 1 an automobile hoist of two-post type including front and rear hoists, with the front hoist having a cylinder l'5 operatively associated with a piston or lift member [6, and a. rear hoist including a cylinder I1 and associated piston l8.

The front hoist is located in a pit l9 formed in a floor surface, indicated generally as 20, and includes a front axle supporting structure or saddle 2|, of a substantially u-shape, fixed to the top of the piston 16 and having a raised axleengaging rib 22 at the free end of each of its legs. A support 23, for an automobile spring pad, also at the free end of each leg of the U- shape channel member 2|, is extended outward; 1y from a corresponding rib 22.

Fig. 4 is an enlarged sectional detail view taken The opening at the top of the pit I9 is of a size and shape such that the saddle member 2!, at the lowermost limit of travel of the piston 46, is received within the pit below the surface of the floor 2t. With the saddle 2i thus located within the pit E3, the pit opening is automatically closed or covered by a pair of floor or cover plates 24 hinged or pivoted at their outer sides 253 for pivotal movement upwardly and away from each other to their open positions, shown in Fig. l, and for movement downwardly toward each other to closed and supported positions on the ribs 22.

When the piston I6 is initially raised, the cover plates 24 are pushed to their open positions by the saddle member 2!. On a continued raising of the piston 56, the inner sides of the cover plates rest against the saddle member 25 and piston l6 so-as to be upwardly inclined toward each other, as shown in Fig. 1, to constitute side guards for the pit opening. This relative position of the cover plates 2 is maintained until the saddle member 2i is lowered into the pit H9, at which time the plates 2d follow the saddle member to their closed positions. It is seen, therefore, that the front hoist, in its lower limit of travel, is located entirely within the pit l9, the opening of which is closed by the plates 23 to provide a floor surface over the pit continuous or flush with the floor 2%. With the piston H in a raised position, the inclination of the plates toward each other over the opening of the pit l9 prevents any accidental slipping by a person into the pit l9.

The rear hoist is mounted in a floor pit 21 and includes a rear axle supporting structure having a transversely extended tubular beam member 28 fixed at its central portion to the top of the piston l3 (Fig. 1). Each end of the tubular beam 28 extends through the central portion of a flat upright longitudinally extended supporting member 2%. The ends of the tubular beam 28 are fixed to a corresponding member 29 by welding and are substantially flush with the outer side surfaces of such members. Rear axle engaging blocks 3! are slidably carried on the top edge of each upright supporting member 29 for movement longitudinally thereof to axle engaging positions.

Adapted to rest on the top of the tubular beam 28, at a position above the piston i8, is a vertically movable cover plate 32 having downward extensions 3% one or" which is shown in Fig. 1, arranged at opposite sides of the piston l8 andguidably extended through the tubular beam 28.

The opening of the rear pit 2'! is of a size and shape such that when the piston I8 is at its lowermost limit of travel the rear axle supporting structure is receivable therein at a position belowthe level of the floor 2B. A closing of the pit opening, when the rear hoist is in either a lowered or raised position, is accomplished by the provision of means including a pair of sta tionary cover members 36 and 31.

With reference to Figs. 1 and 2, it is seen that the cover plates 3% and 3'! are of a substantially rectangular shape with their inner ends 38 spaced from each other to form a transverse opening 39 adapted to receive the transverse beam member 28 therethrough. The outer ends of the stationary plates 36 and iii are connected, as indicated at 4|, to the opposite end walls of the pit opening 2'4. The opposite sides 33 of the cover plates 36 and Si are spaced from the adjacent sidewalls 34 of the pit 277 to form longitudinally extended openings 45, open to the opposite ends oi the transverse opening 39 and adapted to receive the support members 29 therethrough. Fixed adjacent to the inner end of each plate 3% and 37 and projected downwardly therefrom, are a pair of supporting rods 42 the lower ends of which rest on a square shaped flange member 4Q mounted at the top of the cylinder IT. The plates 36 and 37 are thus firmly supported and positioned substantially flush with the floor 26.

With the rear hoist in its lowered position within the pit 2?, the transverse opening 3? is covered over its central portion by the vertically movable cover member 32 which is guidably sup-'- ported in the beam member 23. The remaining end portions of the transverse opening and the longitudinal openings 45, are closed by a pair of oppositely arranged longitudinally extended pivoted. cover members 56 having lateral ears or extensions 43 intermediate their ends which are extended inwardly toward each other at positions overlying the opening 39 at opposite sides of the piston H3. The covers 4% are pivoted at on the upper ends of the pit side walls 34.

In the elevating of the rear hoist from within the pit 21, the cover members it are initially pivotally moved upwardly away from each other, whereby to open the longitudinal openings G5 and the transverse opening 39. On raising of the rear hoist, the cover member is without movement until it is engaged by the tran verse beam member 23. When thus engaged, the cover member 32 is moved upwardly with the rear hoist.

When the hoist is in an elevated position, the cover members 43 are returned to their closed positions, as illustrated in Fig. 1, whereby a garage or service man is free to move about below the rear hoist without danger of slipping into the pit 21.

When the rear hoist is to be lowered, the pivoted cover members 46 are initially moved to their open positions to provide for the of the cross member 28 and the support members 29 within the spaces 39 and 45, respectively. On a lowering of the rear hoist within the pit 21 the cover member 3-2 is engaged in a supported position on the stationary cover members and 37. When the rear hoist is lowered entirely with in the pit 21 below the level of the floor surface 26, the pivoted covers 46 are moved to their closed positions. Thus, as clearly appears in Fig. 2, when the rear hoist is in a lowered posi tion within the pit. 27, the stationary covers 3% and 31, pivoted covers 46, and the vertically movable cover 32 cooperate to completely close the pit opening 2'l.

In order to accomplish an operation of the pivoted covers 46, so that such covers are always in their open positions, when the rear hoist is to be received within, or raised from the pit 2i, and closed at all other times, there is provided a single acting air cylinder 39 (Figs. 3 and 4) having a piston 5| extended outwardly from its'end The cylinder end 53 is pivoted at i ibetween a pair of spaced support members extended rearwardly from a frame member 5? carried adjacent the inner end and from the lower side of the stationary cover member 36. The frame member 5'! forms the base of a substantially U-shape frame structure 58 which includes leg 59 arranged longitudinall of the cover member 36 and extended rearwardly from the frame member 51. It is seen, therefore, that the frame structure 58 and cylinder 49 are supported from the under side of the stationary cover 36 so as to be located within the floor pit 21.

The free end of the piston 5| (Figs. 3 and 4) for the air cylinder 49, is pivoted at 55 to the free end of a rock arm 62 which is carried on a rock shaft 83 at a position intermediate the ends of the rock shaft. The rock shaft 63 is rotatably supported in a pair of oppositely arranged bearing members 64 projected downwardly from the legs 58 of the U-frame 58, at a position adjacent to the rear or free ends of the legs 59. The opposite ends of the rock shaft 63 project outwardly from their corresponding hearings as to positions below the pivoted cover plates as and are provided with rock arms 66. Links or levers Bl are pivotally connected be tween the free ends of the rock arms 66 and the pivoted cover members 46.

On the admission of air under pressure to the cylinder as, through an air inlet connection 69 at its end 52, the piston 5| is moved forwardly, or to the left as viewed in Fig. 4, to in turn provide for a rocking movement of the shaft 63 in a counterclockwise direction, as also viewed in Fig. l, whereby the rock arm 62 is moved from its full line position to its dotted line position, also shown in Fig. 4. This movement of the rock shaft 63 provides for an upward movement of the rock arms 66 from their full line positions to their dotted line positions (Fig. 4) whereby the n links 6? are moved upwardly to provide for an upward pivotal movement of the pivoted cover members :36 away from each other to their open positions.

In their open positions, the pivoted cover memhers are arranged in vertical planes common to the pivots ll so that the transverse opening 39 at opposite sides of the lift member or piston 58, and the longitudinal openings 45 are completely open.

On the release of air from the cylinder 49, the covers flit are initially moved toward each other to their closed positions by the action of a coil sprin ll mounted about the piston 5| and arranged in compression between the cylinder end and a stop collar 72 on the piston 51. After this initial movement of the covers 46 to their closed positions, they are finally moved to their closed positions by the combined action of the spring H and the action of gravity.

The operation of the pivoted covers 46 to their open and closed positions in a timed relation or proper sequence relative to a raising and lowering of the rear lift member is will be best understood from a consideration of Figs. 1 and 7. As previously mentioned, the hoist illustrated is of full hydraulic type and the means for raising and lowering the lift members 16 and IS includes an oil reservoir 53 connected with the front hoist cylinder it through an oil line M and with the rear hoist cylinder ll through an oil line "it, with the oil lines M and 16 having a common connection 15 with the reservoir 13. Oil valves H and 18, for controlling the admission of oil under pressure to the cylinders l5 and ii, respectively, are connected in the oil supply lines ill and '36, respectively, at positions adjacent to each other. The control handles 19 and ill for the valves l1 and 58, respectively, are relatively constructed and arranged so as to be capable of being gripped and operated by one hand for simultaneous operation of the lift members l6 and i8.

Air under pressure is supplied to the oil reservoir l3 and the air cylinder 49 from a suitable source of supply (not shown) through an air supply line 82 having a T-connection 83. A valve structure, indicated generally as 85, includes an air valve unit 86, for, controlling the admission and release of air to the oil reservoir 13, and an air valve unit 86, for controlling the admission and release of air to the air cylinder 49. One end 9i of the T-connection 83 is connected with the air valve unit 86 through a pipe 92, a second end 93 of the T-connection is connected with the air valve unit 81 by a pipe 9 3, with the air Supply line. 82 being connected to the third end 96 of the T-connection. As shown in Figs. 1 and 6, the valve units 88 and El are arranged opposite each other in a substantially parallel relation.

The valveunit 36 (Figs. 6 and 8) includes a pair of like valve members ill and 98 positioned to opposite sides of a pair of transversely spaced pivot supports 99 projected upwardly from the housing or casing ml of the valve unit 3'5. An actuating member ll of a substantially V- shape is pivoted at [52 between the supports 99 and has its free ends I93 arranged to alternately engage the valve stems Hi4 and W6 of the valve members 97 and 98, respectively.

An operating handle lll'l is pivoted at 08 between the upper ends of the supports 99 and is integrally formed adjacent its pivoted end with oppositely arranged pairs of locking members I89, adapted to releasably engage therebetween coacting lock members Ill formed on the actuating member ldl at positions adjacent to the free ends )3 thereof.

The casing Hiilis formed with a longitudinally extended air passage 1 l2, common to the valve members ill and 98, and provided between such valve members with a connection I I3, which is connected with the oil reservoir 13 through an air line or pipe H4.

Whenthe operating handle Iii! is in its neutral or centralposition, shown in full lines in Figs. 6 and 8, both of the valve members ill and S58 are closed and the actuating member I0! is out of contact engagement with the valve stems iil l and To admit air under pressure to the oil H33. reservoir 73, the handle iil'i is moved in a clockwise direction to its dotted line position indicated at A in Fig. 8. This movement of the handle Nil through the actuating member llll depresses the stem member I84 to open the valve member Ql. Air under pressure is thus admitted from the air supply line 82 through the valve 91, passage Hi. and air line lit to the oil reservoir 13.

It is to be noted that the lift members [6 and i8 are not operated on this manipulation of the handle E81, by virtue of the fact that the oil valves Ti and 78 are closed. To maintain the oil in the reservoir 73 under pressure the handle ml is returned to its neutral position.

When air is to be released from the oil reservoir, the handle ldl is moved in a counter-clockwise direction to its dotted line position indicated at B in Fig. 8, whereby the valve member 98 is opened. Air from the reservoir '53 is thus permitted to flow through the air line ll, passage H2 and valve member 98 to the atmosphere through the exhaust outlet I I5 in the valve casing lllii. This release or exhaust of air is stopped by returning the handle It! to its neutral position.

The air valve unit 81 is of a commercially available type, and includes a casing IZll (Figs. 6 and 9) formed with a longitudinal air passage H5 connected at one end with the air line 94 and connected at its other end Ill with the air cylinder 49 through the connection 69.. The air valve 8'! includes further a. double acting valve meam comprised of a lower plunger H9 formed at its lower end with a valve member l2! and an upper plunger :22 of a hollow or tubular construction closed at its upper end but formed adjacent to such upper end with an exhaust port 23. The lower end i2 l of the upper plunger 122 is adapted for sealing engagement "1th the upper end i26 of the lower plunger H9.

The lower end of the upper plunger I22 is normally held. out of a seating engagement with the upper end lit of the lower plunger 1 it by a spring 12? and the valve member i2! is normally retained closed by a spring 128. Thus when the plungers H9 and E22 are in their normal or rest positions, shown in Fig. 9, air is released from the air cylinder 49 through the air connection 69, passage Hi5, upper plunger I22 and then to the atmosphere through the exhaust port i255.

To admit air under pressure to the air cylinder 49, the upper plunger 522 is depressed, Where by the lower end 52 of the upper plunger I22 is seated at the upper end I25 of the lower plunger I I9, and the lower plunger is moved downwardly to open the valve member 82!. Air from the supply line 9 5 is thus permitted to pass through the valve i2! and passage H6 to the air connection 69 for the air cylinder 49.

Pivoted at I29 on the valve unit 81, for up and down pivotal movement, is an actuating lever it! (Fig. 6). In the arrangement of the valve units 86 and 81, the pivot I29 is at a longitudinally spaced position relative to the pivot 582 for he actuating member ii?! of the valve unit 86. Extended laterally in the same direction from the free ends I63 of the actuating member it! are control bars I32 having their free ends adapted for contact engagement with the actuating lever l3l. Thus on movement of the handle Hill to either of its dotted line positions A and B, shown in Fig. one of the control rods H32 engages and moves the actuating lever i3! in a downward direction. The under side of the actuating lever iiil is adapted for contact engagement with the upper end of the plunger H22 in the valve unit 8?. Thus on either the admission or release of air from the oil reservoir 13, as controlled by the manipulation of the handle I Hi, the valve unit 8? is operated to supply air under pressure to the air cylinder at. Whenever the handle it? is in its neutral position, the plunger 122 is released by the actuating lever it! to provide for the exhaust of air from the air cylinder 19.

In the operation of the hoist, assume the ift members It and it to be in their ion tions within the floor pits i9 and El, respectively. The vehicle to be elevated is then driven over the hoist to a centered position determined by the reception of its front wheels in the wheel de tiessions I in (Fig. 1) arranged at opposite sides the front hoist. To raise the lift members, the handle it? is moved to its dotted line position A, shown in Fig. 8. Air under pressure is thus admitted to the oil reservoir '33 through the valve member 9?, and to the air cylinder [it through the valve member iiil. In the manner previously described, the cover members it are moved by the air cylinder is to their open positions.

With the cover members thus opened, the handles 19 and Si for the oil valves iii and "it, respectively, are gripped in one hand and simul taneously moved to their open positions, it be- L ing understood that at this time the handle I0! is gripped by the other hand of the hoist operator, which handle is arranged in close proxas illustrated imity to the oil valves and in Fig. 1.

When the lift members t and it have been elevated to desired position, the oil valves I1 and are closed, and the handle it is returned to its neutral pc 11. With the handle it? in its neutral position, the oil in the reservoir i3 air is released from he air cylinder it a return of the cover members to their closed positions. The pit is thus to permit service or repair work on the vercle, ..out danger of having the service man r r- 1g nto any floor opening.

hen the lift members it and it are to be 'vered, the handle is moved to its dotted n 3, shown to provide for an of the valve me 3 c the valve unit opening of t. ember i2! of. e unit sure is thus provide cover so that valves '3? and "it the rear r heist within the pit the oil .nd are closed, and the handle [01 Air is thus released from the air cylinier it to close over niembei 'f-oin consideration of above description, t invc. es a closure t or pit-mounted "ed relation relathe hoist, so that the hoist is to be :oin. Further,

of a sine and construcfor vehicle to be elevated beon over tl hoist, when the pit an n lilC VSd an open posici under n described and lication to the stood that it is also sting the oil ire-m the inlet e valve structure and fluid connecting the exhaust part 523 with the reservoir.

embodiment thereof, it is to be understood that it ed since changes and modifi. cle therein which are within he full intended scope of t invention, as denne by the appended claims.

I claim:

1.111 full-hydraulic hols member mounted in a door and movable to a lowered. position witl-in pit below the level of the floor surface, means for closing said pit including a pair of oppositely arranged cover members pivotally supported on side walls of said pit for pivotal movement in opposite directions to opening and closing positions relative to said pit, a rock shaft within said pit arranged transversely of said cover members, an air cylinder in said pit having a piston extended longitudinally t including a lift it of said cover members, means connecting said shaft for rockable movement in response to a movement of said piston, means connecting said cover members with said rock shaft for pivotal movement to pit opening and closing positions in response to a rockable movement of said shaft, means for supplying oil under pressure to said lift member including an oil reservoir, an air system for supplying air under pressure to said oil reservoir including a valve structure having air connections with said oil reservoir and air cylinder and air exhaust outlets for said reservoir and air cylinder, a pivoted actuating handle for said valve structure, said valve structure being of a construction such that when said handle is moved to a neutral position therefor air is exhausted from said air cylinder, when said handle is moved in one direction from said neutral posi" tion air under pressure is supplied concurrently to said oil reservoir and said air cylinder, and when said handle is moved in an opposite direction from said neutral position, air is supplied to said air cylinder and exhausted from said oil reservoir, and means operable independently of said valve structure for admitting oil under pres sure from said reservoir to said lift member.

2. In a full-hydraulic hoist including a lift member mounted in a floor pit and movable to a lowered position within the pit, means for closing said pit including a .pair of oppositely arranged pivoted cover members, means pivotally supporting said cover members at the outer sides thereof on a pair of opposite side walls of said pit for pivotal movement in opposite directions to pit opening and closing positions, means for opening and closing said cover members including a rock shaft in said pit arranged transversely of said cover members, means connected between said cover members and said shaft to pivotally move said cover members in response to a rocking movement of said shaft, yieldable means for rocking said shaft in one direction, air-operated means for rocking said shaft in an opposite direction against the action of said yieldable means, means for supplying oil under pressure to said lift member including an oil reservoir and source of air supply under pressure connected with said oil reservoir and said air-operated means, and means for relatively controlling the supply of air from said source to said oil reservoir and said air-operated means such that said cover members are moved to their open positions prior to the movement of said lift member away from raised and lowered positions therefor.

3. In a full-hydraulic hoist having a lift member mounted in a floor pit and movable to a lowered position within said pit below the level of the floor surface, a transverse beam carried adjacent the upper end of said lift member, 1on-- gitudinally extended support members carried at the ends of said beam, means for closing said pit including a pair of stationary members arranged over said pit so as to cover the pit opening over those portions thereof defined by the space between said support members at opposite sides of said beam member, a pair of pivoted cover members arranged at opposite sides of saidstationary members for closing those portions of the pit opening adapted to receive said support members therethrough, a rock shaft in said pit supported from one of said stationary cover memhers and extended between said pivoted cover members, means connected between said pivoted cover members and said rock shaft to open and close said pivoted cover members in response to a rocking movement of said shaft, yieldable means within said pit for rocking said shaft in one direction, air operated means for rockin said shaft in an opposite direction carried on said one stationary cover member and arranged within said pit, means for supplying oil under pressure to said lift member including an oil reservoir and a source of air under pressure connected with said oil reservoir and said air-operated means, and means for relatively controlling the supply of air from said source to said oil reservoir and to said airoperated means such that said pivoted cover members are in their open positions prior to the movement of said lift member away from raised and lowered positions therefor.

4. In a full-hydraulic hoist having a lift member mounted in a floor pit and movable: to a lowered position within said pit below the level of the fioor surface, means for closing the pit opening including a pair of cover members pivotally supported on opposite side walls of said pit for pivotal movement toward each other to closing positions therefor, a rock shaft within said pit extended transversely of said cover :members, a pair of rock arms adjacent opposite ends of said shaft, a third rock arm on said shaft intermediate the ends thereof, pivoted lever systems connected between said pair of rock arms and cover members to provide for the pivotal movement of said cover members in response to a rocking movement of said shaft, air-operated means in said pit connected with said third rock arm to move said shaft in one direction to open said cover members, yieldable means arranged to act on said third rock arm to move,said shaft in an opposite direction toclose said cover members, means for raising and lowering said lift member including an oil reservoir, means for supplying air under pressure to said oil reservoir and air-operated means, and an air control system for relatively controllin the supply of air under pressure to said oil reservoir and airoperated means such that air is admitted to said air-operated means concurrently with the admission of air to or the release of air from said oil reservoir.

5. In a hydraulic vehicle hoist having a lift member mounted in a floor pit and movable to a lowered position within the pit, means for closing said pit including a pair of oppositely arranged cover members pivoted on side walls of said pit for pivotal movement toward each other to closing positions therefor, movable means in said pit connecting said cover members together for concurrent pivotal movement, fluid operated means for moving said movable means in one direction to pivotally move said cover members to open positions therefor, means for raising and lowering said lift member including a source of fluid under pressure, a first means fiuid connecting said. pressure source with said lift member, a second means fluid connecting said pressure source with said fluid operated means, and valve means connect ed in said two fluid connecting means adapted to relatively control the supply of fluid under pressure tosaid lift member and said fluid operated means such that said pivoted cover members are in their open positions prior to the move-; ment of said lift member away from a raised position or a lowered position therefor.

In a full-hydraulic vehicle hoist having a lift member mounted in a floor pit and movable to a lowered position within the pit, means for ClOSillg said pit including a pair of oppositely arranged cover members pivoted on side walls of said, pit for pivotal movement toward each other to closing positions therefor, movable means in said pit connecting said cover members together for concurrent pivotal movement, air-operated means for moving said movable means in one direction to pivotally move said cover members to open positions therefor, means for raising and lowering said lift member including an oil reservoir, a source of air under pressure, air connections from said air source to said 011 reservoir and 10 air-operated means, and air control means arranged in said air connections adapted to relatively control the supply of air from said source to said air-operated means and oil reservoir such that air is admitted to said air-operated means concurrently with the admission of air to or the release of air from said oil reservoir.

HARRY D. SMITH.

No references cited. 

